A N T I M O N Y : ITS HISTORY, CHEMISTRY, MINERALOGY ...

CHAPTER TV.
THE GEOLOGICAL OCCURKEFCE OF ANTIMONY ORES.
THE principal ores of antimony that have any commercial value are :—
L Antimony glance, Sb2S3; also known by the names "gray
antimony ore," " stibnite," or " anthnonite." It contains 714 per
cent, of antimony and 28"6 per cent, of sulphur.
2. Native antimony. It occurs too rarely to be of any commercial
importance.
3. Valcntinite, Sb^O3; the rhombic form of the oxide of antimony,
which is also known as "white antimony" or "antimony bloom."
Tt contains 83*4 per cent, of antimony, and 16*6 of oxygen.
4. tienarmontite, §b2O3; the cubic form of the oxide of antimony.
5. Kermesite, 2Sb2Ss.Sb203; also known as " antimony oxysulphide,"
"red antimony ore," "antimony blende," or "pyrostilbite."
6. Cervantite, Sb.2O4; also known as " antimony ochre."
When antimony ores, specially antimonite, undergo decomposition,
the resulting alteration-products generally are: valentinite,
sonarmontite, kermesite, and cervantite. According to Foullon,
there is a case at Rozsdan in Macedonia where the southern part of
the" vein carries antimony ore, while its northern part carries auripigment
and some realgar. The antimonite has been oxidised to
antimony ochre, valentinite, and red antimony ore, all accompanied
by gypsum and sulphur.
The principal types of antimony doposits are :—*
1, Veins —The ore is generally found disseminated irregularly
in voins of quartz ; sometimes, though rarely, it occurs in lenticular
maHHca. The other gangue materials, besides quartz, are brown spar,
calo-spar, and heavy spar. The products of decomposition of stibnite
aro stiblito, antimony-ochre, valentinite, and senarmontlte; more
rarely, also pyrostibnite, pyrite, bournonite, berthierite, galena, zinc-
* tc Stilmito was one of the minerals formerly cited as having been originated in
veins by volatilisation from lower sources. But it lias probably, in all cases, been
derived from aulutions of alkaline sulphides" [Kemp).